London: On his first state visit to Britain, US President Barack Obama and first lady Michelle Obama were on Tuesday welcomed to Buckingham Palace by Queen Elizabeth II, a media report said.

Obama has a busy round of political talks and meetings during his high profile three-day stay, as well as a lavish state banquet and a meeting with the newly-married Duke and Duchess of Cambridge.

The state visit is only the third by a US president to the UK in 100 years and comes at a time of close cooperation between the two countries on issues ranging from Libya to Afghanistan, counter-terrorism and the Middle East peace process, according to the newspaper.

At the red carpeted Grand Entrance of the palace, President Obama and the first lady were greeted by the monarch and the Duke of Edinburgh.

Expresses grief over tornado

Before he left for the palace, President Obama spoke to reporters, expressing his grief  about the tornado devastation back home in Missouri, Minnesota and around the Midwest, the newspaper said.

'We have been heartbroken by the images we have seen.'

'The devastation is incomparable ... So far we know over 100 people lost their lives ...'

'Our thoughts and prayers are with the families who are suffering at this moment,' the daily quoted Obama as saying.

Prez to meet PM Cameron

Wednesday will be devoted to politics, with talks between Obama and Prime Minister David Cameron at 10 Downing Street, followed by an address to both houses of parliament, in which the president is expected to say that the US has no closer ally in the world than Britain.

The two leaders are also expected to drop in on a barbecue being hosted by their wives, Michelle and Samantha, for families of military personnel involved in joint UK-US missions overseas.

Their meeting with the Obamas was completely private and media were given just a glimpse of the two couples as they left Winfield House to bright sunshine.

All four left in 'The Beast' - the president's armoured limousine - to be taken to Buckingham Palace for their meeting with the queen.

They were then taken to the 1844 room to meet newlyweds William and Kate, where discussions were likely to have covered their recent wedding and honeymoon.